Centre Number Candidate Number General Certificate of Secondary Education 2016 GCSE Chemistry Unit 1 Foundation Tier *GCH11* [GCH11] *GCH11* WEDNESDAY 15 JUNE, AFTERNOON TIME 1 hour 15 minutes. INSTRUCTIONS TO CANDIDATES Write your Centre Number and Candidate Number in the spaces provided at the top of this page. You must answer the questions in the spaces provided. Do not write outside the boxed area on each page or on blank pages. Complete in blue or black ink only. Do not write with a gel pen. Answer all five questions. INFORMATION FOR CANDIDATES The total mark for this paper is 80. Figures in brackets printed down the right-hand side of pages indicate the marks awarded to each question or part question. Quality of written communication will be assessed in Question 3(a)(ii). A Data Leaflet, which includes a Periodic Table of the Elements, is included in this question paper. *24GCH1101* *24GCH1101*
1 Group 1 and 2 elements show a variety of physical and chemical properties. (a) The picture below shows a Group 1 element reacting with water. A lilac flame is observed. lilac flame E. R. Degginger / Science Photo Library (i) State four other observations for this reaction. 1. 2. 3. 4. [4] (ii) Name the Group 1 element which is reacting with water. (iii) Name the two products of the reaction of this Group 1 element with water. [2] *24GCH1102* *24GCH1102*
(b) The diagram below shows part of a mass spectrum of a sample of a Group 2 element. Each peak in the spectrum represents an isotope of this element. 100 90 80 relative abundance 70 60 50 40 30 20 10 0 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 mass (i) What is meant by the term isotope? [2] (ii) Based on the mass spectrum above, how many isotopes of the element are present in the sample? (iii) What is the mass of the isotope with the greatest relative abundance? (iv) Suggest the identity of the Group 2 element using your Data Leaflet. [Turn over *24GCH1103* *24GCH1103*
(v) Suggest one advantage of using mass spectrometry to analyse elements. *24GCH1104* *24GCH1104*
2 Solutions may be classified as acidic, alkaline or neutral using the ph scale. (a) (i) Name an indicator which may be used to find the ph value of a solution. (ii) Complete the following table. Name of Compound Formula ph value H 2 SO 4 Water H 2 O CH 3 COOH 3 [4] (b) Hydrochloric acid reacts with zinc metal to produce a salt and hydrogen gas. (i) Name the salt produced in this reaction. (ii) Describe the chemical test for hydrogen gas and state the result for a positive test. [2] [Turn over *24GCH1105* *24GCH1105*
(c) An excess of hydrochloric acid can build up in the stomach and cause indigestion. Antacid tablets containing calcium carbonate can be taken to relieve the symptoms of indigestion. (i) State the observations made when an antacid tablet containing calcium carbonate is dropped into a beaker of dilute hydrochloric acid. [3] (ii) Write a balanced symbol equation for the reaction between calcium carbonate and hydrochloric acid. [3] *24GCH1106* *24GCH1106*
(d) Other brands of antacid tablets contain aluminium hydroxide. (i) Write the formula of aluminium hydroxide. (ii) State the colour of aluminium hydroxide. (iii) Describe what is observed when sodium hydroxide solution is added until it is in excess to a solution containing aluminium ions. [3] [Turn over *24GCH1107* *24GCH1107*
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3 The Shard in London is 309 metres high and is currently the tallest building in the European Union. It is the fifty-ninth tallest building in the world. chrisdorney / istock / Thinkstock (a) In the construction of the Shard, 12 000 tonnes of steel were used. Steel is an alloy of carbon and iron. One form of carbon is graphite. (i) What is meant by the term alloy? [2] [Turn over *24GCH1109* *24GCH1109*
(ii) Describe the bonding and structure of graphite. In your answer include: the name of the type of bonding, the name of the type of structure, a description of the structure of graphite. In this question you will be assessed on your written communication skills including the use of specialist scientific terms. *24GCH1110* *24GCH1110*
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(b) There are 11 468 panels of glass in the Shard, enough to cover eight football pitches. The glass is made from silicon dioxide, sodium oxide, calcium oxide and small amounts of other compounds, including iron(ii) oxide. (i) What type of bonding is found in silicon dioxide? (ii) What type of bonding is found in sodium oxide? (iii) Using full electronic configurations, draw dot and cross diagrams to show how atoms of calcium combine with atoms of oxygen to form calcium oxide. Include the charge on each ion. [6] *24GCH1112* *24GCH1112*
(c) The glass used in the Shard is low iron glass which is very clear. Any iron(ii) oxide impurity in the glass would produce a tint. (i) What is the formula of iron(ii) oxide? (ii) Iron(II) oxide contains the iron(ii) ion. Complete the table below by giving the number of protons, neutrons and electrons present in an atom of iron and an iron(ii) ion. Atom or ion Atomic number Mass number Number of protons Number of electrons Number of neutrons Fe 26 56 Fe 2+ 26 56 [3] [Turn over *24GCH1113* *24GCH1113*
(d) The Shard uses energy saving methods to generate heat and so its carbon dioxide emissions are reduced. A dot and cross diagram for the bonding in carbon dioxide is shown below. O C O (i) What is the formula for carbon dioxide? (ii) What type of bonding is found in carbon dioxide? (iii) Draw a circle around a lone pair in the dot and cross diagram for carbon dioxide. *24GCH1114* *24GCH1114*
4 The solubility of substances varies with temperature. (a) What is meant by the term solubility? [4] (b) The table below shows the formulae of some compounds. Cu(OH) 2 (NH 4 ) 2 SO 4 KOH CaCO 3 (i) Complete the table below by writing the formulae of the compounds under the headings soluble or insoluble in water. You may find your Data Leaflet useful in answering this question. Soluble Insoluble [2] (ii) State the name of (NH 4 ) 2 SO 4. [Turn over *24GCH1115* *24GCH1115*
(c) The graph below shows the solubility curves for four different substances, A, B, C and D. 80 A 70 Solubility/g/100 g water 60 50 40 30 B C D 20 10 0 0 10 20 30 40 50 60 70 80 90 100 Temperature/ C (i) Which substance (A, B, C or D) is most soluble at 10 C? (ii) Which substance (A, B, C or D) is least soluble at 90 C? *24GCH1116* *24GCH1116*
(iii) At what temperature do substances A and D have the same solubility? (iv) At what temperature would 3g of substance C saturate 10 g of water? Temperature C [Turn over *24GCH1117* *24GCH1117*
5 Seawater contains a range of dissolved salts. (a) (i) Complete the table below for some of the salts present in seawater. Name of Salt Formula Relative Formula Mass MgCl 2 Sodium sulfate Na 2 SO 4 [3] (ii) The most abundant salt present in seawater is sodium chloride, NaCl. Calculate the number of moles of sodium chloride in 29.25 kg. (Relative atomic masses: Na = 23; Cl = 35.5) Moles of NaCl = [3] (iii) Sodium chloride may be obtained by reacting sodium hydroxide with hydrochloric acid. Write a balanced symbol equation for this reaction. [2] *24GCH1118* *24GCH1118*
(b) Magnesium chloride has healing effects on a wide range of diseases. The hydrated form of magnesium chloride contains water of crystallisation and has the formula MgCl 2.6H 2 O. (i) What is meant by the term water of crystallisation? (ii) Calculate the relative formula mass of hydrated magnesium chloride, MgCl 2.6H 2 O. (Relative atomic masses: H = 1; O = 16; Mg = 24; Cl = 35.5) Relative formula mass = (iii) Use the value calculated in (b)(ii) to find the percentage of water of crystallisation in hydrated magnesium chloride. Percentage of water = %[2] [Turn over *24GCH1119* *24GCH1119*
(iv) Describe how water of crystallisation may be removed from hydrated salts and how you would ensure that all of the water of crystallisation has been removed. [2] THIS IS THE END OF THE QUESTION PAPER *24GCH1120* *24GCH1120*
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DO NOT WRITE ON THIS PAGE For Examiner s use only Question Number 1 2 3 4 5 Total Marks Marks Examiner Number Permission to reproduce all copyright material has been applied for. In some cases, efforts to contact copyright holders may have been unsuccessful and CCEA will be happy to rectify any omissions of acknowledgement in future if notified. 204269 *24GCH1124* *24GCH1124*
SYMBOLS OF SELECTED IONS Positive ions Negative ions Name Symbol Name Symbol Ammonium + NH4 Chromium(III) 3+ Cr Carbonate Dichromate 2 CO 3 2 Cr 2 O 7 Copper(II) 2+ Cu Ethanoate CH 3 COO Iron(II) 2+ Fe Hydrogen carbonate HCO 3 Iron(III) 3+ Fe Hydroxide OH Lead(II) Silver Zinc 2+ Zn 2+ Pb Methanoate HCOO + Ag Nitrate NO 3 Sulfate Sulfite 2 4 SO 2 SO 3 SOLUBILITY IN COLD WATER OF COMMON SALTS, HYDROXIDES AND OXIDES DATA LEAFLET For the use of candidates taking Science: Chemistry, Science: Double Award or Science: Single Award Copies must be free from notes or additions of any kind. No other type of data booklet or information sheet is authorised for use in the examinations. All sodium, potassium and ammonium salts All nitrates Soluble Most chlorides, bromides and iodides EXCEPT silver and lead chlorides, bromides and iodides Most sulfates EXCEPT lead and barium sulfates Calcium sulfate is slightly soluble gcse Contents Page Periodic Table of the Elements 2 3 Symbols of Selected Ions 4 Solubility of Common Salts 4 Insoluble Most carbonates EXCEPT sodium, potassium and ammonium carbonates Most hydroxides EXCEPT sodium, potassium and ammonium hydroxides Most oxides EXCEPT sodium, potassium and calcium oxides which react with water chemistry double award single award
7 9 THE PERIODIC TABLE OF ELEMENTS Group 1 1 2 3 4 5 6 7 1 11 12 14 16 19 4 2 20 0 3 23 4 24 5 27 6 28 7 31 8 32 9 35.5 10 40 11 39 12 40 45 48 51 52 55 56 59 59 64 65 13 70 14 73 15 75 16 79 17 80 18 84 19 85 20 88 21 89 22 91 23 93 24 96 25 99 26 101 27 103 28 106 29 108 30 112 31 115 32 119 33 122 34 128 35 127 36 131 37 133 38 137 39 139 * 40 178 41 181 42 184 43 186 44 190 45 192 46 195 47 197 48 201 49 204 50 207 51 209 52 210 53 210 54 222 55 223 56 226 57 227 72 261 73 262 74 263 75 262 76 265 77 266 78 269 79 272 80 285 81 82 83 84 85 86 87 88 89 104 105 106 107 108 109 110 111 112 * 58 71 Lanthanum series 90 103 Actinium series a b x a = relative atomic mass (approx) x = atomic symbol b = atomic number 140 58 232 90 141 59 231 91 144 60 238 92 147 61 237 93 150 62 242 94 152 63 243 95 157 64 247 96 159 65 245 97 162 66 251 98 165 67 254 99 167 68 253 100 169 69 256 101 173 70 254 102 175 71 257 103